1. Field of the Invention
The present invention relates to the safety of medical treatment involving the injection of liquid pharmaceuticals. More particularly, the present invention is related apparatus and procedures for assuring correct use of liquid pharmaceuticals that are administered in injection.
2. Discussion of the Related Art
The problem of assuring that liquid pharmaceuticals are not injected inadvertently through confusion with other liquids that are similar in appearance has become a subject of particular concern recently. Many pharmaceuticals that are administered by I.V. injection are clear, colorless liquids, and almost all of them are water-based. Thus they often are visually indistinguishable from each other. The confusion has produced irreversible harm in some cases: for example, fatal heart failure when a strong muscle relaxant was administered to a patient instead of an anesthetic. The danger of such deadly errors occurring is most acute under operating room and emergency room conditions, where time pressure and the need for effective deligation and coordination among hospital personnel become most acute.
The standard procedure for preventing such misidentification errors in administering injections has been to place a piece of surgical tape on a syringe before a pharmaceutical is drawn into it and to write the name of the drug thereon. Differences in handwriting, the phoenetic and orthographic similarity between the names of pharmaceuticals, and also the smearing and distortion that occur when the water-resistant, textured surface of surgical tape is used to label a syringe, are all sources of error in this procedure. This use of surgical tape is a convenient method but it has proven to be dangerously unreliable.
Furthermore, in present practice a needle is commonly used to withdraw liquids from multi-dose vials. This frequently wastes part of the liquid, which is discarded as being to difficult to extract. Also, since the penetrators are plastic, they are less expensive than needles.